Vegetarian diets reduce the risk of hypertension, according to new research published today in JAMA Internal Medicine by Physicians Committee president Neal Barnard, M.D., and researcher Yoko Yokoyama, Ph.D., M.P.H. The meta-analysis compares blood pressure from more than 21,000 people around the world and finds study participants who follow a vegetarian diet have a systolic blood pressure about 7 mm Hg lower and diastolic blood pressure 5 mm Hg lower than study participants who consume an omnivorous diet.

“Instead of readjusting the definition for hypertension, as was done in the recent guideline revision, let’s write prescriptions for plant-based foods,” says Dr. Barnard. “Compared to antihypertensive drugs, a diet change brings only desirable “side effects,” including healthy weight loss and improved cholesterol, along with the lower blood pressure.”

Hypertensive study participants who combine antihypertensive medications with a plant-based diet lower blood pressure by an average of 5/2 mm Hg in just six weeks.

The meta-analysis shows a foundation of fruits, vegetables, whole grains, and legumes helps study participants keep blood pressure in a healthful range of less than 120/80 mm Hg. For individuals between 40 and 70 years, a 20 mm Hg increase in systolic BP, starting at just 125/75 mm Hg, doubles the risk for heart disease. For comparison, smoking has a similar effect. The Centers for Disease Control and Prevention reports more than 67 million Americans, or one in three adults, have high blood pressure, a risk factor for heart attack, stroke, and kidney disease. The American Heart Association reports high blood pressure is up 27 percent in children and accounts for 350,000 preventable deaths each year.